1. Field of the Invention
The present invention relates to a unit for conveying developer, and more particularly to a developer-conveying unit for conveying toner exhausted from the cleaning unit of an electronic copying machine.
2. Description of the Related Art
In an electronic copying machine, a latent image is formed on a photosensitive drum, and this image is transcribed on a sheet of paper, and developed with toner. The toner which remains on the photosensitive drum after completion of copying of the image, is removed by a cleaning unit. The toner, thus removed, is conveyed by a conveying device into a collection box.
The conveying apparatus comprises a cylindrical conveying duct 100 in which an auger 102 is contained.
The auger 102 is rotatably pivoted to the conveying duct 100 and supported at both ends by bushing 104. The bushings 104 are in direct contact with toner, and, therefore, are stained with toner. The bushings, if stained, disable, in some cases, the conveying auger 102 from rotating. In order to avoid this problem, the bushings must be made of a material to which toner does not stick, or must be sealed to be free from contact with the toner. However, either method is costly.
Further, since both ends of the auger 102 are pivoted, toner cannot be supplied and exhausted in the axial direction of the auger 102. Consequently, the auger 102 cannot be used in a vertical section of the conveying unit shown in FIG. 2. Actually, the toner is made to fall freely, but in some case, part of the toner 106 inevitably sticks to the inner surface of the vertical section 108 as shown in FIG. 3, affecting smooth conveyance of the toner.